If youth knew; if age could.

I have found little that is 'good' about human beings on the whole. In my experience most of them are trash, no matter whether they publicly subscribe to this or that ethical doctrine or to none at all. That is something that you cannot say aloud, or perhaps even think.

It might be said of psychoanalysis that if you give it your little finger it will soon have your whole hand.

A collection to which nothing can be added and from which nothing can be removed is, in fact, dead!

Another technique for fending off suffering is the employment of the displacements of libido which our mental apparatus permits of and through which its function gains so much in flexibility. The task here is that of shifting the instinctual aims in such a way that they cannot come up against frustration from the external world.

The liberty of the individual is no gift of civilization. It was greatest before there was any civilization, though then, it is true, it had for the most part no value, since the individual was scarcely in a position to defend it. The development of civilization imposes restrictions on it, and justice demands that no one shall escape those restrictions.

It is a mistake to believe that science consists in nothing but conclusively proved propositions, and it is unjust to demand that it should. It is a demand made by those who feel a craving for authority in some form to replace the religious catechism by something else, even a scientific one.